Glucagon(Secretion Stimuli)

- Hypoglycemia- Amino acids like arginine

Glucagon(Secretion Inhibitors)

- Hyperglycemia- Insulin- Somatostatin

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Insulin(Synthesis)

- Preproinsulin synthesized in RER- Then cleavage of presignal will produce proinsulin (insulin and C peptide) that is stored in secretory granules

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Insulin(Secretion)

- Increased metabolism of glucose in Beta cells will increase ATP production- ATP will block the ATP sensitive K+ channels which results in generating an action potential (membrane depolarization)- This depolarization will cause Ca++ entry into the cells which in turn causes cleavage of proinsulin and exocytosis of insulin and C peptide equally

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Insulin-dependent glucose transports (Names and Locations)

GLUT-4: in adipose tissue and striated muscles (exercise also increases their expression)

Glucose(Hormonal Control)

- When it is low, glucagon will raise it- When it is very low, epinephrine will release glucose from liver and GH will inhibit GLUT-4 mediated uptake of glucose by the adipose tissue and skeletal muscles- When it remains very low, cortisol will release glucose from liver and also makes amino acids from skeletal muscles available to the liver for gluconeogenesis

Insulin Deficiency(Effects on Na+ and K+)

- Na+: * Losing body stores because of polyuria * May see hypernatremia because of dehydration * May see hyponatremia because of water shift from hyperglycemia - K+: * Moves from intracellular to extracellular (decreased Na+/K+ ATPase activity) * May see initial hyperkalemia * Watch closely after insulin treatment

- State of profound hyperglycemia induced dehydration and increased serum osmolarity. Classically seen in elderly type 2 diabetics with limited ability to drink (can also be seen in type 1)- Thirst, polyuria, lethargy, focal neurological deficits (e.g. seizures), that can progress to coma and death if left untreated

Diabetes Mellitus(Health Maintenance)

- Pneumococcal vaccine- Yearly eye exam to check for proliferative retinopathy- Statin medication if LDL is above 100 mg/dL- ACEIs or ARBs if blood pressure is greater than 130/80 mmHg- ACEIs or ARBs if urine tests +ve for microalbuminuria- Aspirin, used regularly in all diabetic patients above the age of 30- Foot exam for neuropathy and ulcers

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Diabetes Mellitus(Screening recommendations)

- Patients with no risk factors: test HbA1C at age of 45; retest every 3 years if its < 5.7% and no other risk factors develop- Patients with impaired fasting glucose (>110 but less than 125 mg/dL) or impaired glucose tolerance: follow up with frequent retesting

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Diabetes Mellitus(Treatment Goals)

- Tight control of blood glucose in the range of 80-120 mg/dL- HbA1C is less than 8% in children and less than 7% in adults

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Metabolic Syndrome(Factoids)

- Also known as insulin resistance syndrome or syndrome X- Associated with high risk of CAD and mortality from a cardiovascular event